Process for treating hydrocarbon oils



Aug. 7, 1934. w. M. CROSS 1,959,502

PROCESS FOR TREATING HYDROCARBON OILS Filed sept. 1, 192e CRACK/NG TURA/ACE A TTORNEY.

Maggy.

Patented Aug. 7, 1934 Y OFFICE 1,969,502 y PROCESS 4iron,` TREATING HYDRooARBoN 'v f v waueriu. cross, Kansas city, assigner', py; I

mesne assignments, to Gasoline Products vCorng pany, Inc., Wilmington, Del.', a corporation-fof Delaware Application septenabr i, 192s, seriainojjiaais This invention-relates to improvementsA in a process for Vtreatinghydrocarbon oils, and refers primarilyv to a method of vvpurifying Ythe oil vapors in the refluxing or dephlegmating stage .'5`Iby introducing thereto an extraneous gas or air or any medium which will act with the vapors to fractionate out the polymers from the oil' vapors, thereby improving the nal distillate obtained. w

The single gure is a *diagramimaticY side vationallview with parts in section." l i 'Rferringto the drawing, at l's shownaf furnace in which'are positionedthe banks of lcoils 2 and 3; The furnace is preferably heated by means quality of the 1 ele- 4151.' of gas burners not shown.v Four (4) is 'a heavily.

insulated reaction chamber made from a single ingot of forged steel withremovable end plates tov facilitate cleaning; Five (5)`isa secondffur-v nace in the' tube'chamber of which isv positioned the bank of coils 6. 'At'7 is shownarr evaporator' and at 8 is a'bubble tower," the 'lower Aportion 'of 1 which has'been broken away'to sh'ow the interior structure. The tank-like' elementi) -is a 'condenser which is" water-cooleilwater being continuouslyV circu1ated therethrough. The narrow tank `1o is a'gas separatora'nd 11, '12 and 13 are storage tanks. A 1

"The plant'shown is particularly adapted for the treatment of relatively heavy oil, such as' 3 fuel oil, which is supplied from the tank 13 through the line 14 and is charged by means of a pump 15 through line 16 to thepipe still 6-where it is raised to a proper evaporation temperature. The

furnace 5 is heated by gas burnersnot shown.

" The oil, on being discharged from the pipe still, is introduced through the line 1'1 controlled by a valve 18 to the transfer line 19 and thence tillate storage tank 11, the gas separated in the separator 10 being drawn off through the line 25 controlled by a, valve 26 anddirected to storage or for fuel in the furnaces l and 5.

The'unvaporiz'ed material collecting in the bottom of the evaporator is automatically withdrawn by means of a liquid level regulating device 2'l manipulating a valve 28 in thel draw off line 2.94 which conductsthe oil from the bottom`ofthe evaporator tothe -fuel oil storage tank 13, where it may be recycled through the'line 14 to the pipe still- 'or' withdrawn to separate storage or for marketing as fuel-oil. I 1

The reflux condensate which gravitates downwardly through the bubble tower 8, collects in a pool inthe bottom of thetower and is automatically withdrawn by means ofthe liquid level regulating device. 30,"m`alnipulating the valve 31 in.' the draw oil line 32. This reux material is cooled in the condenser box, passing therethrough ina coil 33 and thence througha line B4v to the tank 12. A return pipe 35'from'thetank 12 furnishes a means for recycling the condensate-withdrawn from the bubble'tower'back to a pump 36 which charges itthrough the line 37'to'the.' coils 2 positioned in the top of the furnace from whichthe oil, after being preheated, passes-by the transfer line 38 tothe lower lset of coils 3, thence through a transfer line 39 `tol the lreaction vcham ber-4. -In' the'heatingcoils, the oil is circulated at high velocity` andfhe'ate'dto -a cracking temper--v ature,the heatingoperation being so controlled thatanyconsiderable deposition of carbon in the coils is prevented. In the transfer line `39 is a valve 40. v 1

The heated oil from the coils 2 and 3 at a cracking temperature-is passed tothe enlarged zone 4 where the cracking instituted in the coils is'completed as' a result of the-time factor during which period the oil is maintained in a relatively large -body at a cracking temperature. The pressure-upon the coils and reaction cham-' ber is maintained suniciently high to prevent, insofar as possible, vaporization of the oil. Certain of the lighter fractions having a. critical temperature below this temperature will be more or less in the vapor phase. After reaction in the chamber 4, the oil is withdrawn through the line 19 and the pressure reduced at the valve 41. In the transfer line 19 the cracked products discharged from the reaction chamber and the heated oil from the pipe still 6 are blended and the combined materials discharged into the evaporator where vapors are separated from the blended oil. The vapors as described pass overhead, are dephlegmated in the tower 8 and the uncondensed material finally condensed in the water cooled tank 9 and after gas separation in the element 10, pass to the distillate storage tank 11. l'

Connected into 'the vapor line 20, just priorto the point at -which it enters the tower 8,

oil, introducing the vaporsin .a redux-tower, inf

troduced directly to the tower,the construction*- shown being just merely a matter of convenience.,

The purpose of introducing air or other gases,"

such as ozone, stack gases; hydrogemmarbon? monoxide, sulphur dioxide, or other gaseous ma-'r terials which act chemically, Witbdll oihvapors to fractionate out the polyn1ersl tfp'lrifyf;

make the distillate marketable as motor fu'elhI By introducing a gas at 'thisjunctur'ea'ichemf ical action is brought about between the..hydro-. Y carbon vapors and the gas which increases considerably. thesepa-ration 'of thea polymers in,- the f trays lofI theI bubble tower and' theses polymers, either in solution orv in: suspension, gravitatedownwardlyfwith the condensate:.-and areidrawnv on" from the lowerpooliof the 'bubbleitowerv withthe liquid oil. Subsequentlygothey may.l befc ol.- lectedas settlings inthe storageiftanlmlZor-may pass on and be. retreatedzwith the cracking' stock. in the cracking endl on' thefsystemi. this ocxcurs, normally they. will be separated; out with@ the carbon. and. other.- solid-.or "semi-.solidmaterial. in the reactionchamber from' 'Whiclrrthey-mayz be-easilycleaned.'- f

While. theA introduction ciegas; hasebeen .'shownf -in a. combined. pipe still .and cracking system,

it may, .asfwe1l,. bef used; in. a separatefcrackng unit orin normalpipe.- still.. operation torimprove. the. characteristics. and properties of--theoverheadmaterials.: i i f I-clainr as;'my'inventiom.,; Y i

. 1;..A. method of separating polymerized-.mate-.- rial from; hydrocarbon vapors; comprising,-,suba4A jecting': the; vapors, -.togethen-withan -unheatedf oxidizing gasto refluxactionlin;a-;deph1egmating; tower inv which ithe vapors.- ara-.subjected only.` to; dephlegxnating. action of fractionscondensedz thererom..=

y f 2. A process for treating hydrocarbon oils comprising-heating the: oil-,i passing.. .ther-heated oil into a zone yof lower*pressureftoievaporate'the.

troducing an oxidizing. gas@ directly intofsaid-refflux. tower,. and. subjecting. the. vapors and gas to theY action of; reflux. condensata-to effect reac`` l 1 tion. between the oxidizing gasfa-nd'; thexvapors'- and redux. condensatel toseparatepolymerized-f material therefrom. A

3. A` process. for treating hydrocarbon. oils comprising heating the oil, passing theheated; oil. into a zone of. lower pressure-gto.v evaporate the oil, introducing the vapors together.- with'. an oxidizing gas: into a refiuxtower, and sub jecting the vapors andigas'to the action; of -reflux condensatev to effecti'reaction'-between the oxidizinggas and the. vapors and: neux; conj passing the heated oil toa reaction zone-wherein conversion is. consummated and- 'thef separated polymerized materialissdepositedsf y 4. A process for treating hydrocarbon oiisrcom--;

pri'sing heating the. oil'; passing the heatedfoil into a-zone'of lower pressure toevaporate the oil, in

. and* improve the qualities of distillata Slim. .f inating considerably the necessary treatment to troducing the vapors together with an oxidizing gas into a reflux tower, subjecting the vapors and gas to the action of reiiux condensate to effect reaction between the oxidizing gas and the vapors and reflux .condensate to. separate..,pcly merized material-therefrom, Vremoving'ijemu-x condensate together with the separated polynierized material'irom the tower, heating the same to ,incipient conversion, passing the heated oil to a 'reaction zone wherein conversion is consummated andtl'ie.' separatedi-polymerized material is deposited, and mixing the products of conversion with theheatedoilprior to introducing the same initio.the,.zfoneloflowv pressure.

.i 5..,A` processof.v treating hydrocarbons comprising charging.y oil of relatively diierent molecular weightsto separate stages of treatment, 'subjeotingth'e oil in"one stage to a temperature suicienh-tdistill oi a major portion thereof the. sameto the cracking stage and mixing the:

unyaporiz'ed products from the- Vapoiizing stage; with the -chargingstock supplied tothe distillationstage; Y .f 1" 6" A; processfof.- .treating hydrocarbon-foils.,` comprising- .the steps oijgvaporizingthe oil, subjecting thevapors to arefluxingaction in a dephleg-mating: tower; anduaddingv air directly tosaidv dephlegmating tower vto accelerate-the separation of-polymerizedanaterial.fromthe;vapors. j

fir-process of treating; hydrocarbon oils, come` prising the fstepsf of vapo-rizing; the. oil; subjecting the. vapors to.- af. reflfuxing action l yinf a dephleg= mating towerl and adding -oxidizinggas directlyto said dephlegmating tower to acceleratev `the separation' ofpolymerizedv material -from the vapors.

'8. The process ofj treating hydrocarbonv oils, comprising the steps of subjecting the oil to cracking, vaporizing the volatile products, subjecting the vapors to a reuxing action in a dephlegmating tower, and accelerating the separationof polymerized material from the vapors undergoing dephlegmation by directly introducing anoxidizing medium into the said dephlegmating tower.

9.1.In the'art of treating relatively high'boiling hydrocarbon oils for the production of relatively low boiling distillate oils wherein a hydrocarbon oil is maintained at cracking temperature to -effect substantial conversion of the oil into desired low boiling products, said low boiling products being withdrawn in vapor form after completion of the desired conversion, the said vapors being thereafter dephlegmated to condense and separate therefrom undesired high boiling constituents, and the remaining vapors being final-ly condensed to form the desired low boiling distillate-product, the step of rening said desired low boiling productswhich comprises. intimately contacting the saidvapors with an oxidizing gas introduced directly into the vapors duringthe dephlegmation thereof.

boiling constituents, the remaining vapors being finally condensed to form the desired low boiling distillate products, and the condensed undesired constituents being returned to the oil undergoing conversion, the step of rening said desired low boiling products which comprises intimately contacting the said vapors with an oxidizing gas introduced directly into the vapors during the dephlegmation thereof.

WALTER M. CROSS. 

